1, first measure the size of the sandwich, and determine the length, width and height of the carton according to the size of the sandwich.

2. Then fold the paper so that the long and wide edges can overlap and form an edge as the standard.

3. Fold out one edge of the box.

4. The other side of the paper is also folded with the same diagonal line.

5. Then pinch the two sides of the paper, which will be a little higher.

6. Let's fold in the high part.

7. The sandwich box is ready.